Tubular metallic baseball bats are well known in the art. A familiar example is a tubular aluminum bat. Such bats have the advantage of a generally good impact response, meaning that the bat effectively transfers power to a batted ball. This effective power transfer results in ball players achieving good distances with batted balls. An additional advantage is improved durability over crack-prone wooden bats.
Even though presently known bats perform well, there is a continuing quest for bats with better hitting capabilities. Accordingly, one important need is to optimize the impact response of a bat. Further, it is important to provide a bat with proper weighting so that its swing weight is apportioned to provide an appropriate center of gravity and good swing speed of impact components during use.
Generally speaking, bat performance may be a function of the weight of the bat, distribution of the weight, the size of the hitting area, the effectiveness of force transfer between the handle and the striking barrel, and the impact response of the bat. The durability of a bat relates, at least in part, to its ability to resist denting or cracking and depends on the strength and stiffness of the striking portion of the bat. An attempt to increase the durability of the bat often produces an adverse effect on the bat's performance, as by possibly increasing its overall weight and stiffness, or having less than optimum weight distribution.
It has been discovered that a hitter often can increase bat speed by using a lighter bat, thereby increasing the force transferred to the ball upon impact. Thus it would be advantageous to provide a bat having a striking portion which has sufficient durability to withstand repeated hitting, yet which has a reduced overall bat weight to permit increased bat speed through use of an overall lighter weight bat.
It also has been discovered that greater hitting, or slugging, capability may be obtained by providing a bat with a handle made of a material different from the material of the striking portion or formed in such a manner as to have different capabilities. One manner for providing such is to produce a bat with a composite handle, wherein the composite material may be structured to provide selected degrees of flexibility, stiffness, and strength. For example, in one hitting situation it may be best to have a bat with a more flexible handle, whereas for other hitting situations it is advantageous to have a handle with greater stiffness.
An example of a prior attempt to provide a bat with a handle connected to a barrel section is shown in U.S. Pat. No. 5,593,158 entitled “Shock Attenuating Ball Bat.” In this patent an attempt was made to produce a bat with handle and barrel member separated by an elastomeric isolation union for reducing shock (energy) transmission from the barrel to the handle, and, inherently from the handle to the barrel. Accordingly, such a design does not allow for maximum energy transfer from the handle to the barrel during hitting. As a result, the bat produces less energy transfer or impact energy to the ball due to the elastomeric interconnection between the handle and barrel.
Therefore there is a continuing need for a bat that provides the flexibility of a separate handle member and striking member and maximizes the energy transfer between the two members.
The present invention provides an improved bat with a striking portion with good durability and striking capabilities and a handle portion with desirable weight and stiffness characteristics to permit greater bat speed during hitting.
One embodiment of the invention provides a bat having an elongate tubular striking member with a juncture section which converges inwardly toward the longitudinal axis of the bat on progressing toward an end of the striking member, and an elongate handle member having an end portion thereof which is firmly joined to the converging end portion of the striking member to provide a rigid interconnection therebetween to permit substantially complete striking energy transfer between the handle member and the striking member.
In another embodiment, the bat has an elongate tubular striking member having a juncture section adjacent its proximal end, the striking member being composed of metal having a first effective mass, and an elongate handle member composed of a material having a second effective mass which is less than the first effective mass of the striking member, the handle member having a juncture section adjacent its distal end, with the juncture sections of the striking member and handle member overlapping and being joined together to provide a rigid interconnection therebetween to permit substantially complete striking energy transfer between the striking member and the handle member on hitting. Because the handle member is of a lower effective mass it will help to produce a lighter weight bat with the possibility of a greater swing speed.
The present invention provides a novel bat and method for producing the same wherein the striking portion is comprised of the most appropriate, or optimum, structure for striking and the handle is comprised of the most appropriate, or optimum, structure for swinging, and the two are joined for optimum slugging capability.
The present invention provides a bat, and method for making a bat, wherein selected materials are used in selected portions of the bat to achieve proper weight, or mass, distribution for optimum swing speed and to provide desired strength and stiffness of selected portions.
According to a principal aspect of a preferred form of the invention, a bat has a longitudinal axis and an overall first length, and is capable of being tested with a three-point bend stiffness test device having first and second supports. The bat includes an elongate tubular striking member and a separate handle member. The striking member has a distal end, a proximal end, and a striking region intermediate the distal and proximal ends. The handle member has a distal end and a proximal end, and is coupled to the striking member. The handle member has a resistance to bending along the longitudinal axis of the bat in the range of 10–1000 lbs/in a three-point bend stiffness test wherein the handle member is transversely supported in a first direction by the first and second supports spaced apart a selected distance, with the first support adjacent the distal end and the second support adjacent the proximal end, and the handle member is transversely loaded in a second direction, opposite the first direction, at a location on the handle member in a region between 30% and 40% of the selected distance from the distal end of the handle member.
According to another principal aspect of the present invention, a bat has a longitudinal axis, and is capable of being tested with a three-point bend stiffness test device having first and second supports. The bat includes a non-wooden, one-piece bat frame. The frame includes a distal end, a proximal end, an elongate tubular striking portion, and a handle portion. Either the handle portion or the striking portion includes a tapered region. The frame has a resistance to bending along the longitudinal axis in the range of 10–950 lbs/in a three-point bend stiffness test wherein the frame is transversely supported in a first direction by the first and second supports, wherein the first support is positioned at a first predetermined position, wherein the first predetermined position being the location where the tapered region has a first predetermined outer diameter, wherein the second support positioned a first predetermined distance from the first predetermined position, and wherein the frame is transversely loaded in a second direction, opposite the first direction, on the handle member at a second predetermined position that is located on the handle portion a second predetermined distance from the first predetermined position. The second predetermined distance is between 30% and 40% of the first predetermined distance.
According to another principal aspect of the present invention, a method of categorizing a plurality ball bats includes the following steps. At least two distinct bat categories are created based upon at least one bat characteristic. The at least one bat characteristic includes either the resistance to bending of the frame of the bat or the resistance to bending of the handle portion of the frame of the bat. The method further includes determining the resistance to bending of one of the frame and the handle portion for the plurality of bats. The method also includes assigning one of the at least two categories to each of the plurality of bats based, at least in part, upon either the resistance to bending of the frame or the resistance to bending of the handle portion.
The present invention contemplates producing a handle member with multiple composite layers which are appropriately oriented and joined to provide a handle which has selected strength and stiffness. By providing a bat with a handle member made of composite material which may be laid up in multiple layers with selected orientation and strength, the handle member may be structured to provide selected degrees of strength, flexibility, and vibration transfer in an assembled bat. The present invention also contemplates producing a handle member of a thermoplastic material.
In one embodiment, one of the juncture sections of the striking member or the juncture section of the handle member has projections thereon which extend radially from remainder portions of the juncture section a distance substantially equal to the thickness of a desired layer of adhesive to join the striking member and handle member. Such projections firmly engage the facing surface of the other member and this, in conjunction with the adhesive applied between the two members, provides a firm interconnection therebetween.
This invention will become more fully understood from the following detailed description, taken in conjunction with the accompanying drawings described herein below, and wherein like reference numerals refer to like parts.